diff --git a/cmd/tldr/main.go b/cmd/tldr/main.go
index fbded0e..7339a5e 100644
--- a/cmd/tldr/main.go
+++ b/cmd/tldr/main.go
@@ -4,6 +4,7 @@ import (
 	"os"
 
 	"github.com/TheRootDaemon/tlgc/cmd"
+	"github.com/TheRootDaemon/tlgc/exitcode"
 	"github.com/TheRootDaemon/tlgc/internal/app"
 	"github.com/TheRootDaemon/tlgc/logger"
 )
@@ -12,7 +13,7 @@ func main() {
 	cli, err := cmd.Parse()
 	if err != nil {
 		logger.Error("%v", err)
-		os.Exit(1)
+		os.Exit(exitcode.InvalidArguments)
 	}
 
 	logger.SetDefault(
diff --git a/exitcode/exitcode.go b/exitcode/exitcode.go
new file mode 100644
index 0000000..c977de8
--- /dev/null
+++ b/exitcode/exitcode.go
@@ -0,0 +1,16 @@
+// Package exitcode defines the exit status codes used by tlgc.
+package exitcode
+
+const (
+	// Success indicates that the command completed sucessfully.
+	Success int = iota
+
+	// InvalidArguments indicates that the command was invoked with invalid arguments.
+	InvalidArguments
+
+	// CacheUpdateFailure indicates that updating the cache failed.
+	CacheUpdateFailure
+
+	// LintFailure indicates that the tldr page has lint error(s).
+	LintFailure
+)
diff --git a/internal/app/app.go b/internal/app/app.go
index f8ad6fc..c8dc435 100644
--- a/internal/app/app.go
+++ b/internal/app/app.go
@@ -5,6 +5,7 @@ import (
 	"os"
 
 	"github.com/TheRootDaemon/tlgc/cmd"
+	"github.com/TheRootDaemon/tlgc/exitcode"
 	"github.com/TheRootDaemon/tlgc/internal/config"
 	"github.com/TheRootDaemon/tlgc/locale"
 	"github.com/TheRootDaemon/tlgc/logger"
@@ -89,7 +90,8 @@ func New(opts ...Option) *App {
 // Otherwise the command is delegated
 // to dispatch, whose result becomes the exit code.
 //
-// It returns 0 on success and 1 on error.
+// It returns [exitcode.Success] on success,
+// or the corresponding error-specific exitcode on failure.
 func (a *App) Run(cli *cmd.CLI) int {
 	needsConfig := !cli.GenConfig && !cli.ConfigPath && !cli.ShowVersion && !cli.ShowHelp
 
@@ -103,7 +105,7 @@ func (a *App) Run(cli *cmd.CLI) int {
 	if shouldAutoUpdate(cli) {
 		if err := a.autoUpdate(cli); err != nil {
 			logger.Error("failed to update cache: %v", err)
-			return 1
+			return exitcode.CacheUpdateFailure
 		}
 	}
 
@@ -119,7 +121,8 @@ func (a *App) Run(cli *cmd.CLI) int {
 // win over the bare page-lookup that handles positional arguments in cli.Page.
 // When no case matches, the command is a no-op and returns 0.
 //
-// It returns 0 on success and 1 on error.
+// It returns [exitcode.Success] on success,
+// or the corresponding error-specific exitcode on failure.
 func (a *App) dispatch(cli *cmd.CLI) int {
 	switch {
 	case cli.Update:
@@ -153,7 +156,7 @@ func (a *App) dispatch(cli *cmd.CLI) int {
 	case len(cli.Page) > 0:
 		return a.lookupAndRenderPage(cli)
 	default:
-		return 0
+		return exitcode.Success
 	}
 }
 
diff --git a/internal/app/format.go b/internal/app/format.go
index a7debe9..5871fc5 100644
--- a/internal/app/format.go
+++ b/internal/app/format.go
@@ -6,6 +6,7 @@ import (
 	"path/filepath"
 
 	"github.com/TheRootDaemon/tlgc/cmd"
+	"github.com/TheRootDaemon/tlgc/exitcode"
 	"github.com/TheRootDaemon/tlgc/internal/lint"
 	"github.com/TheRootDaemon/tlgc/logger"
 	"github.com/TheRootDaemon/tlgc/termcolor"
@@ -16,8 +17,8 @@ import (
 // back to the source file, or to a single output file
 // depending on the flags.
 //
-// It returns 0 when every page formatted without lint errors and 1
-// otherwise.
+// It returns [exitcode.Success] when every page formatted without lint errors
+// and 1 otherwise.
 func (a *App) formatPages(cli *cmd.CLI) int {
 	files, err := collectFiles(cli.Page)
 	if err != nil {
@@ -51,7 +52,7 @@ func (a *App) formatPages(cli *cmd.CLI) int {
 	}
 
 	if failed {
-		return 1
+		return exitcode.LintFailure
 	}
 
 	return 0
diff --git a/internal/app/lint.go b/internal/app/lint.go
index 4c2ca5e..04e3645 100644
--- a/internal/app/lint.go
+++ b/internal/app/lint.go
@@ -7,6 +7,7 @@ import (
 	"strconv"
 
 	"github.com/TheRootDaemon/tlgc/cmd"
+	"github.com/TheRootDaemon/tlgc/exitcode"
 	"github.com/TheRootDaemon/tlgc/internal/lint"
 	"github.com/TheRootDaemon/tlgc/logger"
 	"github.com/TheRootDaemon/tlgc/termcolor"
@@ -21,7 +22,7 @@ type lintViolation struct {
 // lintPages runs the linter over every page reachable
 // from the CLI paths and reports each violation to stderr.
 //
-// It returns 0 when every file passed without violations
+// It returns [exitcode.Success] when every file passed without violations
 // and 1 otherwise;
 // a failure to collect or open any file is logged and also yields 1.
 func (a *App) lintPages(cli *cmd.CLI) int {
@@ -56,7 +57,7 @@ func (a *App) lintPages(cli *cmd.CLI) int {
 	}
 
 	if failed {
-		return 1
+		return exitcode.LintFailure
 	}
 
 	return 0
diff --git a/internal/app/update.go b/internal/app/update.go
index 950b19d..c563f6d 100644
--- a/internal/app/update.go
+++ b/internal/app/update.go
@@ -4,6 +4,7 @@ import (
 	"context"
 
 	"github.com/TheRootDaemon/tlgc/cmd"
+	"github.com/TheRootDaemon/tlgc/exitcode"
 	"github.com/TheRootDaemon/tlgc/internal/cache"
 	"github.com/TheRootDaemon/tlgc/internal/config"
 	"github.com/TheRootDaemon/tlgc/internal/upstream"
@@ -12,7 +13,7 @@ import (
 
 // updateCache downloads the latest tldr-pages
 // for the configured languages.
-// Returns 0 on success, 1 on error.
+// Returns [exitcode.Success] on success, [exitcode.CacheUpdateFailure] on error.
 func (a *App) updateCache(cli *cmd.CLI) int {
 	c := cache.New()
 	languages := a.resolveLanguages(cli.Languages)
@@ -20,9 +21,10 @@ func (a *App) updateCache(cli *cmd.CLI) int {
 
 	if err := c.Update(context.Background(), languages, client); err != nil {
 		logger.Error("failed to update cache: %v", err)
-		return 1
+		return exitcode.CacheUpdateFailure
 	}
-	return 0
+
+	return exitcode.Success
 }
 
 // shouldAutoUpdate reports whether a stale cache maybe updated